In a pending U.S. patent application Ser. No. 09/393,562, there is disclosed a ceiling mounted evaporator cabinet that is ideally suited for use in the passenger compartment of a small bus. The housing contains an air inlet located in the floor of the cabinet through which return air from the compartment is drawn into the housing by a tangential blower wheel. The wheel is mounted directly over the air inlet opening and is arranged to direct the incoming air flow over an evaporator coil to condition the air. The conditioned air is then directed out of the front wall of the cabinet back into the passenger compartment.
Because the passenger compartment of a small mini-bus is relatively confined, the passengers can have ready access to the evaporator cabinet and, in particular, to the floor mounted air inlet grill. Foreign objects can be inserted upwardly through the grill into the blower wheel causing damage to the unit and potentially to the person inserting the foreign object into the blower. Most inlet grill to evaporator units are also easily removable so that an air filter, which is typically mounted between the inlet grill, can be periodically replaced when it has become contaminated with dust and dirt. Here again, an easily removable grill can be accidentally or maliciously displaced exposing the blower wheel and other internal components of the housing to potential damage.